Separator plate



2,904,325 Patented Sept. 15, 1959 SEPARATDR PLATE John W. Jones and JackB. Dear, Scottdale, Pa.

Application July 3, 1957, Serial No. 669,886

2 Claims. (Cl. 263--47) This invention relates to the art of heatingmetal coils and is particularly concerned with a new plate for use inseparating and supporting such coils during heating.

Many different types of separators for use with coils while being heatedhave been proposed and several have been used. All such separators withwhich we are familiar have been fabricated by welding narrow, metal barson edge to one or more ring-like plates, that is, plates having axialopenings for the flow of hot gases therethrouugh. Usually the bars curveoutwardly and extend from near the inner periphery to or beyond theother periphery of the plate or plates.

These prior fabricated separators possess certain 1nherentdisadvantages. They are expensive to make because of the cost of thematerial and the cost of fabri eating; they are subjected todifferential expansion and contraction which creates forces tending tobreak the welds; when the bars are between the plates the hot gases donot transfer their heat directly to the coils; and where the plates arebetween the bars, expansion of the coils may exert forces on the barstending to break the welds.

The present invention aims to avoid all these and other disadvantages ofprior separators and attains this aim by providing a cast metalseparator of new form and characteristics.

This invention will be better understood by those skilled in the artfrom the following specification and the accompanying drawings in which:

Fig. 1 is a fragmentary side elevational view partly in section showingseparators embodying the present invention assembled with metal coilsfor use while heating the latter;

Fig. 2 is a plan view of one of the separators of Fig. 1; and

Fig. 3 is a fragmentary sectional view taken on line 33 of Fig. 2.

In Fig. 1, two of the corrugated separators or plates 1 of thisinvention are shown assembled with two coils of strip metal 2, as theymight be assembled in a furnace for heating. Each coil 2 has a centralopening 3 through which heated gases may flow.

The corrugated plate 1 is provided with a central opening defined by aninner periphery 4, the diameter of this opening being slightly less,preferably, than the diameter of opening 3 through the coils and theouter periphery of the plate being slightly greater than that of thecoil so that all the turns of the coils will be supported by the plate.

The plate 1 is a metal casting and consists of suitable heat andoxidation resisting metal, for example, stainless steel. This plate iscorrugated, the corrugations curving outwardly from the inner peripheryon an involute curve of such a nature that the center lines of adjacentcorrugations are substantially parallel for their full length. Thisformation of the corrugations provides valleys between adjacentcorrugations which are of approximately the same width from the innerperiphery of-the plateto the outer periphery andhence atfordpassages of.substantially-uniform cross-sectional area for gases to travel from thecentral opening in the plate along theadjacent .edge of the coilengaging plate. The

gases flow through these valleys with minimum changes in velocitysuch:.as are .traceable to cooling of the gases. As a result, the rate.of 'heat transfer is substantially uniform.

By reason of the corrugations and their curvature the plate may expandand contract without the cracking which occurs in the prior fabricatedseparators.

In Fig. 3 the center lines of the corrugations are indicated at 10 andthe valleys are indicated at 11. The crests of the corrugations haveflat surfaces 12 to provide relatively wide support for the edge of acoil 2 resting thereon. All the crests 12 on one side of the plate liein substantially the same plane and all the crests on the other side ofthe plate lie in substantially another plane with the two planes beingsubstantially parallel to one another.

The plate illustrated in the drawings was five feet in diameter and hada central opening twenty inches in diameter. The inner ends of thecenter lines of the corrugations intersected the inner periphery 4 ofthe plate at 20 intervals. The involute curves for the corrugations weredescribed as follows: A tape was fixed at one of these 20 points and waswrapped about around the inner periphery 4 of the plate. A scribe wasfixed to the free end of the tape and described the involute curve asthe tape was unwound while being kept taut. The center lines of theother corrugations were described in a similar manner by moving thefiXed end of the tape to each of the 20 points. The center lines of thecorrugations so described were approximately 3.49 inches apart and thefiat surfaces of the crests were about /8 inches wide. The plate 1 wasabout 1 /2 inches thick measured from the plane of the crests on oneside to the plane of the crests on the other side thereof.

It will be understood that the foregoing dimensions have been givenmerely for the purpose of illustration and to enable those skilled inthe art to practice the invention. It will also be understood that thethickness and diameter of the plate, as well as the diameter of itscentral opening, maybe varied as desired and that, similarly, the widthof the crests of the corrugations, the spacing between the corrugationsand the precise curvature of the center line of the corrugations may bechanged to suit conditions or as may be desired.

Having thus described this invention in such full, clear, concise andexact terms as to enable any person skilled in the art to which itpertains to make and use the same, and having set forth the best modecontemplated of carrying out this invention, we state that thesubject-matter which we regard as being our invention is particularlypointed out and distinctly claimed in what is claimed, it beingunderstood that equivalents or modifications of, or substitutions for,parts of the above specifically described embodiment of the inventionmay be made Without departing from the scope of the invention as setforth in what is claimed.

What is claimed is:

1. A separator for use with metal coils to be heated, comprising, a castmetal annular plate having an upper and a lower metal surface with asubstantially constant thickness of solid metal therebetween along aradial section of said annular plate, said surfaces being substantiallyparallel and being formed so as to produce corrugations described by aninvolute curve extending from the inner periphery of the annulus to itsouter periphery with the center line of each corrugation beingsubstantially equally distanced for its length from the center line ofcorrugations on each side thereof. i

2. A separator for use with metal coils to be heated, comprising, a castmetal annular plate having an upper and a lower metal surface with asubstantially constant thickness of solid metal therebetween along aradial section of said annular plate, said surfaces being substantiallyparallel and being formed so as to produce corrugations described by aninvolute curve extending from the inner periphery of the annulus to itsouter periphery with the center line of each corrugation beingsubstantially equally distanced for its length from the center line ofcorrugations on each side thereof, each of said cor- References Cited inthe file of this patent UNITED STATES PATENTS Webb Dec. 5, 1933 Dailey,Jr. Nov. 22, 1949 Winder Mar. 9, 1954

